Combined effect of autoclaving-cooling and cross-linking treatments of normal corn starch on the resistant starch formation and physicochemical properties

摘要

Normal corn starch (NCS) was treated by both autoclaving-cooling and cross-linking to produce resistant starch (RS) The RS yield, crystalline structure, as well as other physicochemical properties of the modified starch were investigated The yield of AS was 12 2% by four autoclaving-cooling cycles, and it could be further increased up to 31.0% by the subsequent cross-linking using sodium trimetaphosphate/sodium tripolyphosphate The scanning electron microscopy images clearly illustrated that the granular structure of native starch was disrupted and a continuous network with irregular shape was formed after autoclaving-cooling cycles The subsequent chemical cross-linking appeared to make the network structure more compact and dense. X-ray diffraction patterns showed that B- and V-types coexisted in all the modified corn starches. and all these modified starches exhibited very low viscosity which remained almost constant regardless of temperature changes